The present invention is related to optical networks and, more particularly, to optical transponders for such networks.
Transponders are transceiver (transmitter/receiver) devices which receive signals from a source and retransmit the signals to a destination to operate as relays. As described herein, the transponders provide the interfaces between WDM optical transport networks, such as metropolitan area networks (MANs) and wide area networks (WANs), and clients, such as local area networks (LANs) and storage area networks (SANs). It should be noted that these networks are exemplary only and should not be considered limiting. Furthermore, the term, WDM (wavelength division multiplexing), is used inclusively as to include DWDM (dense WDM) and other optical networks where wavelength is used to define the communication channels.
Heretofore, a transponder unit mapped a single client interface to a single optical network channel interface. With many different client and network protocols, such as (in increasing bit transfer rates) DS-1/E1, DS-3/E3, 10/100Base-T, OC-3/STM-1 to OC-12/STM-4, Gigabit Ethernet, OC-48/STM-16, OC-192/STM-64, and 10 Gigabit Ethernet network protocols, some transponders units were capable of adapting to several protocols. Such flexibility avoided the need for separate transponder units for each protocol combination and lowered network costs.
Nonetheless, a transponder unit provides only a mapping for one client interface and one network channel interface. It would seem beneficial if a transponder unit could provide a mapping for multiple client and network channel interfaces. Furthermore, it would be beneficial if the mapping could be reconfigurable. The present invention provides for such a transponder unit.